Reflectometer and method for manufacturing a reflectometer

Abstract

A reflection-type graduation having a silicon substrate. The silicon substrate has first subsections formed thereon. Each of the first subsections has etched oblique surfaces. The surfaces are positioned so that light beams directed incident to the surfaces cause no retroreflection. The substrate also includes second subsections having relatively higher reflecting properties as compared to the first subsections. The first subsections and second subsections are alternatively disposed on the substrate in a first direction.

1. A reflection graduation, comprising:
 a silicon substrate; 
 first subsections disposed on the substrate, each of the first subsections having etched oblique surfaces, the surfaces positioned such that light beams directed incident to the surfaces cause no retroreflection; and 
 second subsections having relatively higher reflecting properties as compared to the first subsections; 
 wherein the first subsections and the second subsections are alternately disposed on the substrate in a first direction; 
 wherein each first subsection includes at least one secondary V-shaped groove that extends in a second direction, perpendicular to the first direction, along nearly an entire length of an edge of each first subsection; and wherein the second subsections are substantially planar. 
 
     
     
       2. The reflection graduation as recited in  claim 1 , wherein the oblique surfaces include a plurality of adjacent V-shaped grooves disposed in the second direction, each groove including a first surface and a second surface. 
     
     
       3. The reflection graduation as recited in  claim 2 , wherein the grooves are regularly spaced in the first subsections. 
     
     
       4. The reflection graduation as recited in  claim 2 , wherein the first surface and the second surface of each groove are oriented at an angle of approximately 72° to one another. 
     
     
       5. The reflection graduation as recited in  claim 1 , wherein the silicon substrate includes monocrystalline silicon, and wherein the first direction corresponds to a direction of the monocrystalline silicon. 
     
     
       6. The reflection graduation as recited in  claim 1 , wherein a width in the first direction of each first subsection is equivalent to a width in the first direction of each second subsection. 
     
     
       7. The reflection graduation as recited in  claim 1 , wherein the oblique surfaces form pyramid-shaped depressions. 
     
     
       8. The reflection graduation as recited in  claim 1 , wherein the oblique surfaces are positioned so that a light beam directed thereon from a direction of incidence reflects from the oblique surfaces in a direction that coincides with a direction other than the direction of incidence. 
     
     
       9. The reflection graduation as recited in  claim 1 , wherein the second subsections include a coating of highly reflective material. 
     
     
       10. The reflection graduation as recited in  claim 1 , wherein the second subsections do not include oblique subsections. 
     
     
       11. A reflection graduation, comprising:
 a silicon substrate; 
 first subsections disposed on the substrate, each of the first subsections having etched oblique surfaces, the surfaces positioned such that light beams directed incident to the surfaces cause no retroreflection; and 
 second subsections having relatively higher reflecting properties as compared to the first subsections; 
 wherein the first subsections and the second subsections are alternately disposed on the substrate in a first direction; and 
 wherein the second subsections include a coating of highly reflective material. 
 
     
     
       12. The reflection graduation as recited in  claim 11 , wherein the oblique surfaces include a plurality of adjacent V-shaped grooves disposed in a second direction perpendicular to the first direction, each groove including a first surface and a second surface. 
     
     
       13. The reflection graduation as recited in  claim 12 , wherein the grooves are regularly spaced in the first subsections. 
     
     
       14. The reflection graduation as recited in  claim 12 , wherein the first surface and the second surface of each groove are oriented at an angle of approximately 72° to one another. 
     
     
       15. The reflection graduation as recited in  claim 12 , wherein each first subsection includes at least one secondary V-shaped groove that extends in the second direction along nearly an entire length of an edge of each first subsection. 
     
     
       16. The reflection graduation as recited in  claim 11 , wherein the silicon substrate includes monocrystalline silicon, and wherein the first direction corresponds to a direction of the monocrystalline silicon. 
     
     
       17. The reflection graduation as recited in  claim 11 , wherein a width in the first direction of each first subsection is equivalent to a width in the first direction of each second subsection. 
     
     
       18. The reflection graduation as recited in  claim 11 , wherein the oblique surfaces form pyramid-shaped depressions. 
     
     
       19. The reflection graduation as recited in  claim 11 , wherein the oblique surfaces are positioned so that a light beam directed thereon from a direction of incidence reflects from the oblique surfaces in a direction that coincides with a direction other than the direction of incidence. 
     
     
       20. A method for manufacturing a reflection graduation, comprising the steps of:
 providing a silicon substrate; and 
 forming first subsections and second subsections that alternately extend in a first direction on the silicon substrate, the first subsections and the second subsections having different optical reflecting properties, 
 in the first subsections, a plurality of oblique surfaces being produced by deep etching, the oblique surfaces positioned such that no retroreflection of the light beams incident thereto results; and 
 providing a coating of highly reflective material on the second subsections. 
 
     
     
       21. The method as recited in  claim 20 , further comprising the step of forming a plurality of V-shaped grooves in a second direction perpendicular to the first direction. 
     
     
       22. The method as recited in  claim 21 , wherein the forming step includes the substep of selectively etching oblique surfaces into the silicon substrate using an etching solution in a region of the first subsections. 
     
     
       23. The method as recited in  claim 22 , further comprising the step of covering at least the second subsections with an etching mask on the silicon surface prior to the forming step. 
     
     
       24. The method as recited in  claim 23 , wherein the etching mask includes chromium. 
     
     
       25. The method as recited in  claim 22 , wherein the etching solution includes potassium hydroxide in combination with isopropanol. 
     
     
       26. The method as recited in  claim 22 , wherein the etching step continues until each of the V-shaped grooves is completely formed. 
     
     
       27. The method as recited in  claim 20 , further comprising the step of etching a plurality of pyramid-shaped depressions into the silicon substrate in the first subsections. 
     
     
       28. A method for manufacturing a reflection graduation, comprising the steps of:
 providing a silicon substrate; and 
 forming first subsections and second subsections that alternately extend in a first direction on the silicon substrate, the first subsections and the second subsections having different optical reflecting properties; 
 wherein, in the first subsections, a plurality of oblique surfaces is produced by deep etching, the oblique surfaces positioned such that no retroreflection of the light beams incident thereto results; 
 wherein each first subsection includes at least one secondary V-shaped groove that extends in a second direction, perpendicular to the first direction, along nearly an entire length of an edge of each first subsection; and 
 wherein the second subsections are substantially planar. 
 
     
     
       29. The method as recited in  claim 28 , further comprising the step of forming a plurality of V-shaped grooves in the second direction perpendicular to the first direction. 
     
     
       30. The method as recited in  claim 29 , wherein the forming step includes the substep of selectively etching oblique surfaces into the silicon substrate using an etching solution in a region of the first subsections. 
     
     
       31. The method as recited in  claim 30 , further comprising the step of covering at least the second subsections with an etching mask on the silicon surface prior to the forming step. 
     
     
       32. The method as recited in  claim 31 , wherein the etching mask includes chromium. 
     
     
       33. The method as recited in  claim 31 , further comprising the step of removing the etching mask after completion of the forming step. 
     
     
       34. The method as recited in  claim 30 , wherein the etching solution includes potassium hydroxide in combination with isopropanol. 
     
     
       35. The method as recited in  claim 30 , wherein the etching step continues until each of the V-shaped grooves is completely formed. 
     
     
       36. The method as recited in  claim 28 , further comprising the step of etching a plurality of pyramid-shaped depressions into the silicon substrate in the first subsections.